This study investigates the inherent variability in the viscoelastic properties, specifically the complex modulus and phase angle of unmodified asphalt binder. Understanding these properties is essential for highlighting the performance-based behavior of asphalt binders. Despite the very controlled environment in which tests for these properties are done, variability persists due to its complex nature. This might contribute to uncertainties in the pavement response. In this research, fifteen samples of unmodified VG10 asphalt binder were subjected to frequency sweep tests across various temperatures and loading frequencies. The experimental data enabled the construction of a frequency and temperature master curve using the WLF equation and a sigmoidal model. The temperature master curve was also drawn using a modified version of the WLF equation. Variability in the complex modulus and phase angle values was quantitatively evaluated using statistical indicators, which include coefficient of variation, interquartile range, interdecile range, and interpercentile range. The results indicated a significant variability in the lower reduced frequency for complex modulus and the reverse trend for phase angle. While in temperature master curves, the variability was relatively higher in lower temperatures for both complex modulus and phase angle. These findings underscore the necessity for enhanced understanding and control of binder properties to mitigate the impact on pavement performance.